Colorectal cancer is the third most frequent type of cancer in the world having an occurrence of about 1 million new cases every year. The incidents of cancer are considerably more frequent in the industrial part of the world.
Current techniques for mechanically performing anastomosis of hollow organs use circular mechanical staplers, which execute the connection of the tissue edges of the dissected hollow organ by metallic or plastic staples. A wide variety of surgical staplers have been developed for gastric, oesophageal and intestinal surgery. In performing surgical anastomotic stapling, generally two pieces of the hollow organ are joined by a ring of staples with a closed loopstapler. End to end anastomoses are generally performed by intraluminal surgical staplers that deliver a pair of staggered rings of staples. During this process, a circular knife blade is used to separate the tissue that is held within the circular ring. The separated tissue is then removed with the stapler to form a circular opening within the lumen along the stapling line.
A major issue regarding anastomosis healing is the blood circulation of the anastomosis during the healing process. Despite substantial development of surgical techniques during the last decades, morbidity and mortality after resections in the gastrointestinal tract, e.g. due to anastomotic leakage, remain as serious problems. Ischemia and inflammation, which are natural parts of the healing process, may cause leakage and secondary infection that may be fatal for the patient in the stapling area. Therefore, it has become common practice to relieve the pressure from the anastomosis by performing a deviating stoma, especially when the anastomosis is carried out in the lower part of colon and in rectum. By relieving pressure and faecal stream from the anastomosis during the healing process, the leakage incident may be reduced and fatal consequences of anastomotic dehiscence can be avoided. The inconvenience for the patient is obvious, since the patient must have a temporary stoma for a time period of about 3 to 6 months, and then has to undergo a second surgery in order to close the stoma. Unfortunately in many cases, the closure of the stoma cannot be reversed and the patient is forced to live with a permanent stoma leading to lower quality of life associated with increased costs.
Additionally, there is an increased risk of anastomotic stenosis, surgical staplers create a smaller and more rigid opening compared to the cross section of the original lumen due to the staples inside the hollow structure connecting the two ends thereof, i.e. a collar may be formed that may lead to stenosis.
Hence, there has been a need in the technical field to develop assemblies overcoming these disadvantages. One such assembly is disclosed in WO 2007122223, wherein an assembly comprising interlocking members for use in achieving anastomosis of tubular organs is disclosed. The assembly comprises two rigid parts, onto which two elastic rings are arranged, to secure intestine ends, respectively, in between each rigid part and corresponding elastic part, whereafter the rigid parts are interconnected via a connection member. It is however difficult to use such open end anastomotic rings for connecting the side of an intestine to another side or an open end, which is often called for due to tumours with difficult access.